int a[8];
char *day[]={"","MONDAY","TUESDAY","WEDNESDAY","THURSDAY","FRIDAY","SATURDAY","SUNDAY"};
main()
{//lekai
    int i,t,j;
    a[4]=6;
    for(i=1;i<=3;i++){
        a[i]=2;
        if(!a[i+3])a[i+3]=7;
        else {a[i]=0;continue;}
        for(t=1;t<=3;t++){
            if(!a[t])a[t]=5;
            else continue;
            if(!a[t+2])a[t+2]=4;
            else{a[t]=0;continue;}
            for(j=5;j<7;j++){
                if(!a[j])a[j]=3;
                else continue;
                 if (!a[j+1])a[j+1]=1;
            else{a[j]=0;continue;}
            for(i=1;i<=7;i++)
            printf("Doctor %c is on duty %s.\n",'A'+a[i]-1,day[i]);
            exit(0);
            }
           
        }
    }
}